International Business Machines Corporation
Staircase patterning for 3D NAND devices

Abstract:

Semiconductor devices and methods of forming the same include forming an etch mask on a stack of alternating dielectric layers and conductor layers. An exposed portion of a dielectric layer and a conductor layer is etched away to form a wordline. The forming and etching steps are repeated, adding additional etch mask material at each iteration, to form respective wordlines at each iteration.